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| author | Peter Zijlstra <peterz@infradead.org> | 2013-09-11 12:43:13 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-11-29 11:11:42 -0800 |
| commit | e895dad0a5b1db5475346d9c2ae4a92e6fefa58d (patch) | |
| tree | 5a1333b355a74c688a911fb2926c127236b55cef /arch/x86 | |
| parent | 5bad04d7bc7fe12a89b716f8b63d32b5735f6dd2 (diff) | |
| download | linux-3.10-e895dad0a5b1db5475346d9c2ae4a92e6fefa58d.tar.gz linux-3.10-e895dad0a5b1db5475346d9c2ae4a92e6fefa58d.tar.bz2 linux-3.10-e895dad0a5b1db5475346d9c2ae4a92e6fefa58d.zip | |
sched, idle: Fix the idle polling state logic
commit ea8117478918a4734586d35ff530721b682425be upstream.
Mike reported that commit 7d1a9417 ("x86: Use generic idle loop")
regressed several workloads and caused excessive reschedule
interrupts.
The patch in question failed to notice that the x86 code had an
inverted sense of the polling state versus the new generic code (x86:
default polling, generic: default !polling).
Fix the two prominent x86 mwait based idle drivers and introduce a few
new generic polling helpers (fixing the wrong smp_mb__after_clear_bit
usage).
Also switch the idle routines to using tif_need_resched() which is an
immediate TIF_NEED_RESCHED test as opposed to need_resched which will
end up being slightly different.
Reported-by: Mike Galbraith <bitbucket@online.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: lenb@kernel.org
Cc: tglx@linutronix.de
Link: http://lkml.kernel.org/n/tip-nc03imb0etuefmzybzj7sprf@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/process.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 81a5f5e8f14..59b90379cb6 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -391,9 +391,9 @@ static void amd_e400_idle(void) * The switch back from broadcast mode needs to be * called with interrupts disabled. */ - local_irq_disable(); - clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); - local_irq_enable(); + local_irq_disable(); + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); + local_irq_enable(); } else default_idle(); } |